1. CNGS Project Overview
Konrad Elsener

2. 3. Status / Schedule / Cost 4. Summary
CNGS Overview
OUTLINE
1. Introduction to CNGS
2. Expected performance
3. Status / Schedule / Cost
4. Summary

3. Experiments at Gran Sasso:
CNGS Overview
1. Introduction
- CERN and LNGS (“the Gran Sasso Laboratory”) exist
the physics of “long base-line” neutrino experiments is
interesting (scient. committees: SPSC, LNGSC, SPC, etc.)
decision by Council Dec. 1999: build CNGS facility
first experiment: nm beam -> nt appearance
Experiments at Gran Sasso:
OPERA
ICARUS

4. CNGS Overview 10 cm long graphite rods (13 segments, interspaced);
total length 2 m; F = 5 / 4 mm
400 GeV protons from SPS,
fast extracted ( 2 x 10 ms)

5. CNGS Overview 150 kA F=2.45 m steel tube, t = 18 mm
surrounded by 50 cm concrete;
vacuum 1 mbar
entrance window 2mm Ti
exit window 12 mm steel (?)
180 kA

6. CNGS Overview
800 m m m m
V = 1 litre air-filled ionisation chambers
(17 fixed + 1 moveable detector
in both muon detection chambers)

7. CNGS Overview

9. 2. Expected Performance CNGS Overview cf. “Addendum” of 1999:
priority to LBL nt appearance -
SBL experiment “out”
-> result: “lower energy” beam -more compact layout of target / horn / reflector
cf. “Note” of Dec. 2000:
-> higher current in reflector
-> space after target for monitor

10. cost reduction CNGS Overview SPS supercycles for CNGS running
with Fixed Target or LHC filling
CNGS + fixed target
cost reduction
CNGS + LHC

11. For 1 year of CNGS operation (200 days) we expect:
CNGS Overview
For 1 year of CNGS operation (200 days) we expect:
(4.8x1013 protons in SPS, 55% efficiency )
protons on target “nominal” x 1019
nm in 100 m2 at Gran Sasso x 1012
nm “charged current” events per 1000 t  2500
(n + N -> N’ + m)
nt events (from oscillation)  20 “detectable”

12. Potential for upgrade of CNGS intensity exists: (protons on target)
CNGS Overview
Potential for upgrade of CNGS intensity exists:
(protons on target)
“nominal” “upgrade”
2 times 2.4x times 3.5x per extraction
(cf. SL Seminar by R. Cappi, 21 March 16:00 in SL auditorium)
“nominal” “ultimate” = not very realistic
4.5 x x per year
200 days, mixed running, days, dedicated running, % efficiency (using 2.4) % efficiency (using 2.4) % efficiency (using 3.5)

13. “A world of differences” between APPEARANCE and DISAPPEARANCE
Sept / May 2001:
CNGS: effects of alignment errors
– study the needs of remotely controlled movements
Examples: effect on nt cc events
horn off axis < 3%
by 6 mm
reflector off axis 3%
by 30 mm
proton beam on target < 3%
off axis by 1 mm
CNGS facility misaligned < 3%
by 0.5 mrad (beam 360 m off)
“A world of differences”
between
APPEARANCE
and
DISAPPEARANCE
experiments !
Conclusion: For CNGS performance, the main issues are
(a) the geodesic alignment wrt. LNGS
(b) the beam must hit the target
(--> horn / reflector have no motorized supports)

14. 3a. Status and Schedule
CNGS is on schedule !

15. Excavated

16. CNGS Overview
4 March 11:00

18. 3b. Schedule / Cost CNGS Overview
1) In the present difficult financial situation of CERN, all non-LHC
activities are being scrutinized. One of the measures proposed
is to have a complete stop of the SPS from October 2004 to
April 2006.
2) Soon after the approval of the CNGS facility, it appeared
to be “impossible” to build CNGS for the originally estimated
cost of 71 MCHF. Today, the cost estimated is about 79 MCHF.

19. 4. Summary CNGS Overview CNGS CE excavations well under way
--> CNGS is “on schedule” (but...)
CNGS estimated cost has increased (71 -> 79 MCHF)
--> our major problem today ...
Present schedule: FIRST BEAM IN SPRING 2006

20. … and finally:
many thanks to all !